Given line equation of 2-order:
$$5 x^{2} + 4 x y + 8 y^{2} - \frac{4 \sqrt{5} x}{5} + \frac{\sqrt{10} y}{4} + 32 = 0$$
This equation looks like:
$$a_{11} x^{2} + 2 a_{12} x y + a_{22} y^{2} + 2 a_{13} x + 2 a_{23} y + a_{33} = 0$$
where
$$a_{11} = 5$$
$$a_{12} = 2$$
$$a_{13} = - \frac{2 \sqrt{5}}{5}$$
$$a_{22} = 8$$
$$a_{23} = \frac{\sqrt{10}}{8}$$
$$a_{33} = 32$$
To calculate the determinant
$$\Delta = \left|\begin{matrix}a_{11} & a_{12}\\a_{12} & a_{22}\end{matrix}\right|$$
or, substitute
$$\Delta = \left|\begin{matrix}5 & 2\\2 & 8\end{matrix}\right|$$
$$\Delta = 36$$
Because
$$\Delta$$
is not equal to 0, then
find the center of the canonical coordinate system. To do it, solve the system of equations
$$a_{11} x_{0} + a_{12} y_{0} + a_{13} = 0$$
$$a_{12} x_{0} + a_{22} y_{0} + a_{23} = 0$$
substitute coefficients
$$5 x_{0} + 2 y_{0} - \frac{2 \sqrt{5}}{5} = 0$$
$$2 x_{0} + 8 y_{0} + \frac{\sqrt{10}}{8} = 0$$
then
$$x_{0} = \frac{\sqrt{10}}{144} + \frac{4 \sqrt{5}}{45}$$
$$y_{0} = - \frac{5 \sqrt{10}}{288} - \frac{\sqrt{5}}{45}$$
Thus, we have the equation in the coordinate system O'x'y'
$$a_{11} x'^{2} + 2 a_{12} x' y' + a_{22} y'^{2} + a'_{33} = 0$$
where
$$a'_{33} = a_{13} x_{0} + a_{23} y_{0} + a_{33}$$
or
$$a'_{33} = - \frac{2 \sqrt{5} x_{0}}{5} + \frac{\sqrt{10} y_{0}}{8} + 32$$
$$a'_{33} = - \frac{2 \sqrt{5} \left(\frac{\sqrt{10}}{144} + \frac{4 \sqrt{5}}{45}\right)}{5} + \frac{\sqrt{10} \left(- \frac{5 \sqrt{10}}{288} - \frac{\sqrt{5}}{45}\right)}{8} + 32$$
then The equation is transformed to
$$5 x'^{2} + 4 x' y' + 8 y'^{2} - \frac{2 \sqrt{5} \left(\frac{\sqrt{10}}{144} + \frac{4 \sqrt{5}}{45}\right)}{5} + \frac{\sqrt{10} \left(- \frac{5 \sqrt{10}}{288} - \frac{\sqrt{5}}{45}\right)}{8} + 32 = 0$$
Rotate the resulting coordinate system by an angle φ
$$x' = \tilde x \cos{\left(\phi \right)} - \tilde y \sin{\left(\phi \right)}$$
$$y' = \tilde x \sin{\left(\phi \right)} + \tilde y \cos{\left(\phi \right)}$$
φ - determined from the formula
$$\cot{\left(2 \phi \right)} = \frac{a_{11} - a_{22}}{2 a_{12}}$$
substitute coefficients
$$\cot{\left(2 \phi \right)} = - \frac{3}{4}$$
then
$$\phi = - \frac{\operatorname{acot}{\left(\frac{3}{4} \right)}}{2}$$
$$\sin{\left(2 \phi \right)} = - \frac{4}{5}$$
$$\cos{\left(2 \phi \right)} = \frac{3}{5}$$
$$\cos{\left(\phi \right)} = \sqrt{\frac{\cos{\left(2 \phi \right)}}{2} + \frac{1}{2}}$$
$$\sin{\left(\phi \right)} = \sqrt{- \cos^{2}{\left(\phi \right)} + 1}$$
$$\cos{\left(\phi \right)} = \frac{2 \sqrt{5}}{5}$$
$$\sin{\left(\phi \right)} = - \frac{\sqrt{5}}{5}$$
substitute coefficients
$$x' = \frac{2 \sqrt{5} \tilde x}{5} + \frac{\sqrt{5} \tilde y}{5}$$
$$y' = - \frac{\sqrt{5} \tilde x}{5} + \frac{2 \sqrt{5} \tilde y}{5}$$
then the equation turns from
$$5 x'^{2} + 4 x' y' + 8 y'^{2} - \frac{2 \sqrt{5} \left(\frac{\sqrt{10}}{144} + \frac{4 \sqrt{5}}{45}\right)}{5} + \frac{\sqrt{10} \left(- \frac{5 \sqrt{10}}{288} - \frac{\sqrt{5}}{45}\right)}{8} + 32 = 0$$
to
$$8 \left(- \frac{\sqrt{5} \tilde x}{5} + \frac{2 \sqrt{5} \tilde y}{5}\right)^{2} + 4 \left(- \frac{\sqrt{5} \tilde x}{5} + \frac{2 \sqrt{5} \tilde y}{5}\right) \left(\frac{2 \sqrt{5} \tilde x}{5} + \frac{\sqrt{5} \tilde y}{5}\right) + 5 \left(\frac{2 \sqrt{5} \tilde x}{5} + \frac{\sqrt{5} \tilde y}{5}\right)^{2} - \frac{2 \sqrt{5} \left(\frac{\sqrt{10}}{144} + \frac{4 \sqrt{5}}{45}\right)}{5} + \frac{\sqrt{10} \left(- \frac{5 \sqrt{10}}{288} - \frac{\sqrt{5}}{45}\right)}{8} + 32 = 0$$
simplify
$$4 \tilde x^{2} + 9 \tilde y^{2} - \frac{\sqrt{2}}{36} + \frac{61057}{1920} = 0$$
Given equation is imaginary ellipse
$$\frac{\tilde x^{2}}{\left(\frac{\sqrt{- \frac{\sqrt{2}}{36} + \frac{61057}{1920}}}{2}\right)^{2}} + \frac{\tilde y^{2}}{\left(\frac{\sqrt{- \frac{\sqrt{2}}{36} + \frac{61057}{1920}}}{3}\right)^{2}} = -1$$
- reduced to canonical form
The center of canonical coordinate system at point O
____ ___ ____ ___
\/ 10 4*\/ 5 5*\/ 10 \/ 5
(------ + -------, - -------- - -----)
144 45 288 45
Basis of the canonical coordinate system
$$\vec e_{1} = \left( \frac{2 \sqrt{5}}{5}, \ - \frac{\sqrt{5}}{5}\right)$$
$$\vec e_{2} = \left( \frac{\sqrt{5}}{5}, \ \frac{2 \sqrt{5}}{5}\right)$$